Page 128 - Migraine, the heart and the brain

Chapter 7
movements larger than the 2 x SD of the 500 ms pre-CS period were considered as signi cant and further categorised into auditory startle response (latency to peak 10–150 ms) and cerebellar conditioned responses (CRs; latency to peak 150-600 ms). The peakamplitude for all responses was expressed as the percentage of the averaged peak-amplitude in all US-only trials for that participant. Arrows indicate: 1 unconditioned response (UR) peak-amplitude, 2 CR peak-amplitude, 3 CR onset, 4 CR peak-time, 5 UR onset, 6 UR peak-time, and 7 2 x SD of 500 ms pre-CS baseline period. (c) Examples of raw data traces obtained from a control (anthracite line) and FMH1 patient (red line). In US-only trials (upper panel) controls and FMH patients show a normal reflexive eyelid closure. In paired (middle panel) and CS-only trials (lower panel) controls show large amplitude and perfectly timed CRs, i.e. the peak of the CR is exactly at the point where the US is delivered. FHM1 patients show CRs, but those CRs have much smaller amplitudes. In addition, the timing of their CRs is severely impaired in that they start too early and therefore reach the maximum eyelid closure too early. (d) Right panels. Peak timing of CRs over all eight training blocks per group. Controls, and migraine patients with and without aura show a clear preference in the peak-time of their CR around the US onset. FHM1 patients completely lack this timing aspect in their CRs (asterisk). Left panels. For comparison we plotted the peak timing of URs over all eight training blocks in US-only trials, in which no difference was found between the four groups. (E) CR onset over all eight training blocks per group. FHM1 patients have CRs that started signi cantly earlier than CRs in controls, migraine patients with and without aura. (f) CR peak-amplitude over all eight training blocks per group. FHM1 patients have signi cantly smaller CR amplitudes than controls and migraine patients with and without aura. (g) No difference was found between groups in the CR percentage before training (block 1) and after training (maximum percentage in either block 6, 7 or 8). FHM1: familial hemiplegic migraine type 1.
When including participants with FHM1 in a fourgroup comparison with controls and participants with migraine with or without aura, pitch angle velocity (F (3,164) = 24.1, p < 0.001) and pitch angle (F (3,164) = 13.3, p < 0.001) were signi cantly different. Post hoc analysis using the Bonferroni-test showed that for the two-legged stance condition the mean pitch angle velocity (4.2; SD 2.2) and pitch angle (2.2; SD 0.8) for participants with FHM1 were signi cantly higher than those in controls and participants with migraine with or without aura (Figure 4). These differences remained so after adjustments for BMI and age (see Model 1 in Table 6). None of the participants with FHM1 could complete the one-legged stance step condition. When evaluating all six individual tasks of this test separately, sway measurements were signi cantly increased in both pitch and roll directions in participants with FHM1 compared to the other groups (Table 6). During the walking condition post hoc comparisons using the Bonferroni-test indicated that the mean pitch velocity for participants with FHM1 (40.6 degrees per sec, SD 7.7) was signi cantly higher compared to controls (31.9 degrees per sec, SD 9.4) and participants with migraine (30.2 degrees per sec, SD 8.6) or without aura (28.2 degrees per sec, SD 8.8). These differences remained signi cant after adjusting for age and BMI.
126